INFLUENCE OF BIOCHAR FROM PAPER FIBER SLUDGE AND CEREAL HUSKS ON SOIL WATER CONTENT.

The paper is focused on the effect of biochar amendment on the soil water content. Biochar used for the field experiment was produced from paper fiber sludge and grain husks (1:1 w/w) by pyrolysis at 550°C for 30 minutes. The field study was conducted at the experimental site in Nitra region Slovakia (lat. 48°19´00´´, lon. 18°09´00´´). The biochar was incorporated into the soil (0-10 cm) in spring 2014. The plots (4m x 6m) were organized in randomized block design. The experiment consisted of 5 levels of biochar application 0, 10 and 20 t/ha (B0, B10, B20) and biochar with N-fertilizer 160 kg N ha-1 (B10+N, B20+N) with 3 replicates. The field had been cropped with corn (Zea mays L.) using conventional tillage. The soil moisture was determined from disturbed soil samples (depth 5-10 cm) by the gravimetric method every week during the growing season (March 2015 - October 2015). The available water storage in the top layer (0.1 m) of the soil profile was higher at all variants with applied biochar as compared to control, reaching the highest cumulative water storage at the higher dose of biochar (20 t ha-1). The total cumulative water storage ranged in the order: Control < B10 < B10+N < B20 < B20+N, resp. 504.4 < 703.5 < 735.0 < 744.2 < 747.4 mm. The difference in the cumulative water content during this specific period varied from +199 (B10) up to +243 mm (B20). [ABSTRACT FROM AUTHOR]